I owned a 5.7 at the same time as my aac pilot. (not rated for 5.7) At the time Elite ammo was providing threaded barrels and subsonic ammo. There was some discussion (2008/09) about the efficacy of suppressing the pistol vs the PS90.

People preferred suppressing the ps90 over the pistol. Suppressing the pistol did help mitigate the fireball during low light shooting. There were some extraction issues when suppressed with the pistol. This is all from memory, so take it with a grain of salt. I am betting the extraction issues were due to back pressure. The other big issue at the time was that no 22lr cal can was rated for the cartridge. Folks were using their 223/556 cans. There might be some now, but I think most of the ones i have seen are only rated 5.7 for the rifle, not the 5" pistol.

Isn't the sparrow rated for 5.7 as well (down to the pistol length)? They have been around for sometime now from silencerco.

I also looked into this about 7 years ago or so when I had a five seven. Just decided it wasn't worth the cost of admission between a new barrel, extra 22lr can to take it, and not much of a great end result on it (always underwhelmed with most suppressed pistols anyway besides 22). On a ps90 that's been cut down, that'd be a different story then. A buddy did that to his and it's a blast to shoot.

It just wasnt very quiet to me. I took a couple of shots without ear pro and didn't like it. I think a can with a little more volume would have been a quieter combo....or it probably would have been great with subsonic ammo, but subs were just a little to expensive for what I wanted to spend.

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